The present invention is drawn to a coupling device for locking and unlocking the fifth-wheel kingpin of a semitrailer. Heretofore fifth-wheel couplings previously used by locking and unlocking the kingpin of the fifth-wheel were designed as forgings and were extremely heavy in order to absorb the forces encountered during the locking and unlocking operation. Typical coupling devices comprised a lever having a locking projection which engaged a coupling claw for locking and unlocking the fifth-wheel kingpin. The lever was designed as a two-arm lever having relatively small leverage thereby leading to the necessity for large weighty forgings. It is known in the prior art to provide a locking bar for holding the coupling claw in place instead of a locking lever as noted above. Employing a locking bar reduced the overall weight of the coupling; however, the locking bar required a complex guide mechanism for locking the coupling claw in place.
Naturally it would be highly desirable to provide a coupling device for locking and unlocking the fifth wheel kingpin of a semitrailer which is simple and light in both construction and operation.
Accordingly, it is a principal object of the present invention to provide a coupling device for locking and unlocking the fifth-wheel kingpin of a semitrailer.
It is a further object of the present invention to provide a coupling device as set forth above which is efficiently designed and simple to operate.
Further objects and advantages of the present invention will appear hereinbelow.